The general rule of thumb is 300 kms per hop for 5 - 20 mhz, as I understand it. VOAarea, ICEarea, and REC533 programs basically agree with me, but these are skywave numbers.
SW (using groundwave) is almost like AM / MW to a point, with dipoles. Vertical Dipoles (ground screen or not) seem to, as you go higher in frequency, have launch angles that begin to approach the horizon. Still, except for several EU nations that have used dipoles for European service -- dipoles are not commonly used on SW. ----- Original Message ----- From: "Thomas Giella KN4LF" <[EMAIL PROTECTED]> Subject: [HCDX] Groundwave Propagation On SW Groundwave propagation distance is definitely dependent upon transmitter power, transmission mode, vertical antenna design and ground conductivity. Horizontal antennas produce virtually no ground or surface wave broadside to the antenna but they do produce some off of the ends. [ ...] You might expect to see the following approximate ground or surface wave distances for given frequencies: 350 kc 400 miles 540 kc 200 miles 1800 kc 100 miles 3000 kc 60 miles 7000 kc 40 miles 28000 kc 10 miles Over water is a totally different story. At day on the beach at Cape Canaveral, FL you can here the MF AM broadcast band 50 KW stations in New York City at an approximate distance of 1000 miles. 73, Thomas F. Giella Space & Atmospheric Weather Forecaster ---[Start Commercial]--------------------- World Radio TV Handbook 2003 is out! Order it now! http://www.amazon.com/exec/obidos/ASIN/0823059677/hardcoredxcom ---[End Commercial]----------------------- ________________________________________ Hard-Core-DX mailing list [EMAIL PROTECTED] http://dallas.hard-core-dx.com/mailman/listinfo/hard-core-dx http://www.hard-core-dx.com/ _______________________________________________ THE INFORMATION IN THIS ARTICLE IS FREE. It may be copied, distributed and/or modified under the conditions set down in the Design Science License published by Michael Stutz at http://dsl.org/copyleft/dsl.txt
